Replace GitLab CI with Gitea Actions workflows

GitLab CE was migrated off to reduce memory pressure on the host, so
.gitlab-ci.yml is dead. Split into one workflow file per site (shared,
40k-rankings, aos-rankings, kingmaker, scouting, events) since Gitea/
GitHub Actions path filters are workflow-level, not job-level like
GitLab's rules.changes. Build+deploy are combined into a single job per
site rather than separate build/deploy stages, since both run on the
same host and there's no need to round-trip artifacts between them.

The weekly ELO refresh job's schedule (Wed 02:00 Atlantic/Azores) is
approximated as a fixed 02:00 UTC cron, since Actions cron has no DST
handling.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.gitea/workflows/refresh-elo.yml

@@ -0,0 +1,30 @@
+name: Weekly ELO Sync
+
+# Original GitLab pipeline schedule ran Wednesdays 02:00 Atlantic/Azores.
+# Actions cron is always UTC with no DST handling, so this is a fixed
+# approximation (02:00 UTC) rather than an exact equivalent year-round.
+on:
+  schedule:
+    - cron: '0 2 * * 3'
+  workflow_dispatch:
+
+jobs:
+  refresh:
+    runs-on: host
+    steps:
+      - uses: actions/checkout@v4
+      - name: Refresh ELO data
+        working-directory: sites/40k-rankings/statcheck-elo-scraper
+        run: python3 refresh_elo.py
+      - name: Commit and push if changed
+        env:
+          GITEA_ACCESS_TOKEN: ${{ secrets.GITEA_ACCESS_TOKEN }}
+        run: |
+          git config user.email "gitea-actions@gateway-gamers.net"
+          git config user.name "Gitea Actions"
+          git remote set-url origin "https://mandalore:${GITEA_ACCESS_TOKEN}@gl.mando.club/mandalore/gateway-gamers.net.git"
+          git add sites/40k-rankings/public/elo-data.json
+          if ! git diff --cached --quiet; then
+            git commit -m "data: refresh stat-check ELO rankings"
+            git push origin HEAD:main
+          fi